Genera Energy considers switchgrass to be one of the primary dedicated energy crops for the production of biofuels and biochemicals. The appeal of this native perennial grass is that it can be densely planted and high yielding while requiring a minimal amount of inputs like fertilizer and weed control once it has been established. These and other characteristics make it an ideal crop for many biomass supply chains.
Switchgrass is ideal for planting into no-till seed beds with sufficient moisture for seed emergence. Seed planting depths range anywhere from ¼ to ½ inch and are critical to the success of the stand. Another critical factor is ensuring good seed distribution which means it is important to ensure that your drill has small seed boxes suitable for accurately metering your switchgrass seed.
Controlling competing grasses and other broad-leaf weeds early in the establishment year is critical. We recommend careful evaluation of each field as the weed control measures can vary greatly depending on previous crop history and specific weed conditions. There are few herbicides that are labeled for grassy weed control and some are not allowed on certain classes of land. Weed control begins prior to planting. We typically have one or two burn down applications of a glyphosate herbicide to kill the existing cover, with the first application in the fall prior to planting. Once the switchgrass has emerged, Cimarron can be used to control any broad leaf weeds.
Switchgrass in a biomass supply chain system should be harvested once a year. It is best to wait for the first killing frost before harvesting, as this helps to dry the plant out and also reduces nutrient removal. Switchgrass should be cut at least 6 inches high to maintain the vitality of the stand. Switchgrass can be harvested with conventional hay equipment including both round and square balers as well as forage harvesters.
Switchgrass can take three full seasons before it reaches full maturity. In the first year, yield estimates are around 30 percent (2 dry tons per acres) of the full yield potential. The second year reaches about 70 percent (5 dry tons per acre). At full maturity by the third year, a reasonable expectation is anywhere from 6 to 8 dry tons per acre, however there have been yields of up to 10 dry tons per acre. All of these yields depend on several factors including soil quality, access to moisture, and nutrient uptake.
Switchgrass can be the right fit for your supply chain, along with many other crops. Contact Genera Energy today to learn more about switchgrass as well as our supply chain services.
By Marshall Hauser, Feedstock Information Systems Developer
